While the senior team is in freefall, winning just three of their last 12 matches, it seems the kids are more than all right.

Last summer was the first time France had reached the final, never mind lifted the trophy, in the tournament’s 11-year history.

Centre Romain Ntamack and prop Demba Bamba, 19 and 20 respectively, have already graduated to the senior side. Ntamack started last weekend’s defeat by Wales. Bamba is in the XV to take on England this Sunday.

Jordan Joseph and Cameron Woki – hard-carrying back-row products of Parisian side RC Massy – and the impish Carbonel may not be far behind.

Like France’s football world champions, the victorious under-20s side drew on the nation’s multi-cultural heritage.

Could they, like their football counterparts, be a generation to drag France back to the height of the international game?

Former France fly-half Thomas Castaignede won the first of his 54 Test caps as a 20-year-old.

“It is very exciting,” he told BBC Sport.

“Everyone is excited because we need to rebuild, French rugby is in the worst position at the moment and these young players can bring a new philosophy to the game.

“Some players are coming from different social levels and that is good for us, because these guys know hard work.

“They know what it is to come from a low point to take every step to reach the highest level. We can be proud of that.”

Freddie Michalak and Clement Poitrenaud, either side of Itay’s Mirco Bergamasco, were part of another crop of promising France players

But we have been here before.

“I remember in November 2001, I went down to Toulouse, to interview Freddie Michalak, Clement Poitrenaud and Nicolas Jeanjean,” says Gavin Mortimer, who played semi-professionally in France before swapping the dressing room for the press box.

“They were all either 19 or 20 and had just played for France in that autumn’s Tests, but really none of them kicked on. Michalak, to me, sums up French rugby over the past 20 years,

“He had all the talent, but did not have the application or the temperament. It was faintly embarrassing when he went to Toulon, alongside Jonny Wilkinson, in 2012.

“The two are roughly the same age and have been compared in the past, but when you looked at what they had achieved it was chalk and cheese.

“That has been the story of French rugby in the professional era.”

It is difficult to deny the narrative.

The World Under-20 Championships replaced a similar under-21 event.

A France team containing Lionel Beauxis, Maxime Medard, Damien Chouly and Maxime Mermoz lifted that crown in 2006, but failed to make the same impression at senior level.

In 2012, an 18-year-old Gael Fickou marked his Heineken Cup debut with a wonderfully impudent try against Leicester. He was hailed as a future global superstar. He may yet be, but so far that status has eluded him.

Yacouba Camara made his international debut as a much-hyped 21-year-old in February 2016, but Sunday will be only his 11th Test start.

Another flanker, Sekou Macalou, tore apart the All Blacks defence in a midweek second-string friendly in 2017, but disappeared from international view soon after.

France has given youth its head. Of the 12 teenagers to have appeared in the Six Nations, half have been French. They have been less keen to give it time and support though.

“The leaders haven’t really been there. It is a big step for the young players and they can be a bit lost,” said Castaignede.

Castaignede, aged 20, dropped the match-winning goal against England in Paris in 1996

“When things are going wrong you need to turn and look at one of the oldest players and find out what we are going to do now.”

If France are short on leadership on the pitch, on the touchline there has been a carousel of mediocrity. Jacques Brunel is the fourth national team coach in less than eight years.

“There is a certain conservatism in French rugby; they are the only Six Nations team never to appoint a foreigner as a head coach and it shows. They have appointed this succession of old men frankly,” adds Mortimer.

“France did well in the amateur era because it was amateur. Serge Blanco could get away with smoking 40 a day, but rugby is now fought in the gym and in the players’ diets and the French have not been able to adapt.

“When Brunel was appointed, they had the chance to go for a foreigner – there was talk of Nick Mallett – and find someone who is not going to get bogged down in the huge politics of French rugby, but it didn’t happen.”

Young French players are often big fish in small ponds with fat wallets. The incentive to prove themselves on the international scene may not be as obvious as for their counterparts elsewhere.

There is hope, though, that the coming generation could be different. Not because of any innately superior talent, but thanks to more favourable circumstances.

There are now quotas, punishable by points deductions, for home-grown players in top-flight squads and the prospect of a home World Cup in 2023 is focusing minds on opening up the pathway from age-grade sides to the national team.

Rory Teague, the Englishman who coached Bordeaux until November, is sceptical whether intentions will be backed up by action.